CVE-2026-6426

A type mismatch vulnerability was found in QEMU's vhost inflight migration VMState handling. The destination buffer size is stored as a uint64_t but read by the VMS_VBUFFER load path as a signed int32_t. On little-endian hosts, a crafted incoming migration state with bit 31 set causes the value to be interpreted as negative and then implicitly converted to a very large size_t, leading qemu_get_buffer() to copy migration-stream data beyond the bounds of the mmap-backed inflight region. This can result in a crash of the QEMU process or memory corruption. Exploitation requires control of the migration producer or write access to the migration channel, combined with a destination configured to use vhost inflight migration.

CVSS v3 4.4 MEDIUM

4.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.7 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-6426
https://bugzilla.redhat.com/show_bug.cgi?id=2513498

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 22:17

Updated : 2026-08-31 18:17

NVD link : CVE-2026-6426

Mitre link : CVE-2026-6426

CVE.ORG link : CVE-2026-6426

JSON object : View

Products Affected

No product.

CWE

CWE-681

Incorrect Conversion between Numeric Types

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